/**
 * 国密SM3加密{JS实现}
 * 
 * 参考 https://blog.csdn.net/Shen_yuanjia/article/details/111879819
 * 
 * @returns
 */
function SM3() {
	if (!(this instanceof SM3)) {
		return new SM3();
	}
 
	this.reg = new Array(8);
	this.chunk = [];
	this.size = 0;
 
	this.reset();
}
 
SM3.prototype.reset = function() {
	this.reg[0] = 0x7380166f;
	this.reg[1] = 0x4914b2b9;
	this.reg[2] = 0x172442d7;
	this.reg[3] = 0xda8a0600;
	this.reg[4] = 0xa96f30bc;
	this.reg[5] = 0x163138aa;
	this.reg[6] = 0xe38dee4d;
	this.reg[7] = 0xb0fb0e4e;
	this.chunk = [];
	this.size = 0;
};
 
/**
 * 字符串转byte数组
 */
SM3.prototype.strToBytes= function (s) {
  var ch, st, re = [];
  for (var i = 0; i < s.length; i++ ) {
    ch = s.charCodeAt(i);  
    st = [];                 
    do {
      st.push( ch & 0xFF );  
      ch = ch >> 8;          
    }
    while ( ch );
    re = re.concat( st.reverse() );
  }
  return re;
};
 
SM3.prototype.write = function(msg) {
	var m = (typeof msg === 'string') ? this.strToBytes(msg) : msg;
	this.size += m.length;
	var i = 64 - this.chunk.length;
	if (m.length < i) {
		this.chunk = this.chunk.concat(m);
		return;
	}
 
	this.chunk = this.chunk.concat(m.slice(0, i));
	while (this.chunk.length >= 64) {
		this._compress(this.chunk);
		if (i < m.length) {
			this.chunk = m.slice(i, Math.min(i + 64, m.length));
		} else {
			this.chunk = [];
		}
		i += 64;
	}
};
 
/**
 * 计算hash值
 */
SM3.prototype.sum = function(msg, enc) {
	if (msg) {
		this.reset();
		this.write(msg);
	}
 
	this._fill();
	for (var i = 0; i < this.chunk.length; i += 64) {
		this._compress(this.chunk.slice(i, i + 64));
	}
 
	var digest = null;
	if (enc == 'hex') {
		digest = "";
		for (var i = 0; i < 8; i++) {
			digest += this.reg[i].toString(16);
		}
	} else {
		var digest = new Array(32);
		for (var i = 0; i < 8; i++) {
			var h;
			h = this.reg[i];
			digest[i * 4 + 3] = (h & 0xff) >>> 0;
			h >>>= 8;
			digest[i * 4 + 2] = (h & 0xff) >>> 0;
			h >>>= 8;
			digest[i * 4 + 1] = (h & 0xff) >>> 0;
			h >>>= 8;
			digest[i * 4] = (h & 0xff) >>> 0;
		}
	}
 
	this.reset();
	return digest;
};
 
SM3.prototype._compress = function(m) {
	if (m < 64) {
		console.error("compress error: not enough data");
		return;
	}
	var w = this._expand(m);
	var r = this.reg.slice(0);
	for (var j = 0; j < 64; j++) {
		var ss1 = this._rotl(r[0], 12) + r[4] + this._rotl(this._t(j), j)
		ss1 = (ss1 & 0xffffffff) >>> 0;
		ss1 = this._rotl(ss1, 7);
 
		var ss2 = (ss1 ^ this._rotl(r[0], 12)) >>> 0;
		var tt1 = this._ff(j, r[0], r[1], r[2]);
		tt1 = tt1 + r[3] + ss2 + w[j + 68];
		tt1 = (tt1 & 0xffffffff) >>> 0;
		var tt2 = this._gg(j, r[4], r[5], r[6]);
		tt2 = tt2 + r[7] + ss1 + w[j];
		tt2 = (tt2 & 0xffffffff) >>> 0;
		r[3] = r[2];
		r[2] = this._rotl(r[1], 9);
		r[1] = r[0];
		r[0] = tt1;
		r[7] = r[6]
		r[6] = this._rotl(r[5], 19);
		r[5] = r[4];
		r[4] = (tt2 ^ this._rotl(tt2, 9) ^ this._rotl(tt2, 17)) >>> 0;
	}
 
	for (var i = 0; i < 8; i++) {
		this.reg[i] = (this.reg[i] ^ r[i]) >>> 0;
	}
};
 
SM3.prototype._fill = function() {
	var l = this.size * 8;
	var len = this.chunk.push(0x80) % 64;
	if (64 - len < 8) {
		len -= 64;
	}
	for (; len < 56; len++) {
		this.chunk.push(0x00);
	}
 
	for (var i = 0; i < 4; i++) {
		var hi = Math.floor(l / 0x100000000);
		this.chunk.push((hi >>> ((3 - i) * 8)) & 0xff);
	}
	for (var i = 0; i < 4; i++) {
		this.chunk.push((l >>> ((3 - i) * 8)) & 0xff);
	}
};
 
SM3.prototype._expand = function(b) {
	var w = new Array(132);
	for (var i = 0; i < 16; i++) {
		w[i] = b[i * 4] << 24;
		w[i] |= b[i * 4 + 1] << 16;
		w[i] |= b[i * 4 + 2] << 8;
		w[i] |= b[i * 4 + 3];
		w[i] >>>= 0;
	}
 
	for (var j = 16; j < 68; j++) {
		var x;
		x = w[j - 16] ^ w[j - 9] ^ this._rotl(w[j - 3], 15);
		x = x ^ this._rotl(x, 15) ^ this._rotl(x, 23);
		w[j] = (x ^ this._rotl(w[j - 13], 7) ^ w[j - 6]) >>> 0;
	}
 
	for (var j = 0; j < 64; j++) {
		w[j + 68] = (w[j] ^ w[j + 4]) >>> 0;
	}
 
	return w;
};
 
SM3.prototype._rotl = function(x, n) {
	n %= 32;
	return ((x << n) | (x >>> (32 - n))) >>> 0;
};
 
SM3.prototype._t = function(j) {
	if (0 <= j && j < 16) {
		return 0x79cc4519;
	} else if (16 <= j && j < 64) {
		return 0x7a879d8a;
	} else {
		console.error("invalid j for constant Tj");
	}
};
 
SM3.prototype._ff = function(j, x, y, z) {
	if (0 <= j && j < 16) {
		return (x ^ y ^ z) >>> 0;
	} else if (16 <= j && j < 64) {
		return ((x & y) | (x & z) | (y & z)) >>> 0;
	} else {
		console.error("invalid j for bool function FF");
		return 0;
	}
};
 
SM3.prototype._gg = function(j, x, y, z) {
	if (0 <= j && j < 16) {
		return (x ^ y ^ z) >>> 0;
	} else if (16 <= j && j < 64) {
		return ((x & y) | (~x & z)) >>> 0;
	} else {
		console.error("invalid j for bool function GG");
		return 0;
	}
};
 
/**
 * 等效于Array.from目的是做浏览器兼容处理 Array.from IE浏览器不支持
 */
SM3.prototype.toArray = function(s, f){
	var a = [];
	for(var i=0; i<s.length; i++){
		var t  = s[i];
		if(f){
			t = f(t);
		}
		a.push(t);
	}
	return a;
};
 
/**
 * SM3加密主函数
 * 
 * @param msg
 * @returns
 */
function sm3Digest(msg){
	var _sm3 = new SM3();
    var digest = _sm3.sum(msg);
	console.log(digest)
    var hashHex = _sm3.toArray(digest, function(byte) {return ('0' + (byte & 0xFF).toString(16)).slice(-2);}).join('');
    return hashHex;
}